// SPDX-License-Identifier: GPL-3.0-or-later

#define NETDATA_RRD_INTERNALS
#include "rrd.h"

#if RRD_STORAGE_TIERS != 5
#error RRD_STORAGE_TIERS is not 5 - you need to update the grouping iterations per tier
#endif

static void rrdhost_streaming_sender_structures_init(RRDHOST *host);

bool dbengine_enabled = false; // will become true if and when dbengine is initialized
size_t storage_tiers = 3;
bool use_direct_io = true;
size_t storage_tiers_grouping_iterations[RRD_STORAGE_TIERS] = {1, 60, 60, 60, 60};
size_t storage_tiers_collection_per_sec[RRD_STORAGE_TIERS] = {1, 60, 3600, 8 * 3600, 24 * 3600};
double storage_tiers_retention_days[RRD_STORAGE_TIERS] = {14, 90, 2 * 365, 2 * 365, 2 * 365};

size_t get_tier_grouping(size_t tier) {
    if(unlikely(tier >= storage_tiers)) tier = storage_tiers - 1;

    size_t grouping = 1;
    // first tier is always 1 iteration of whatever update every the chart has
    for(size_t i = 1; i <= tier ;i++)
        grouping *= storage_tiers_grouping_iterations[i];

    return grouping;
}

RRDHOST *localhost = NULL;
netdata_rwlock_t rrd_rwlock = NETDATA_RWLOCK_INITIALIZER;

time_t rrdset_free_obsolete_time_s = 3600;
time_t rrdhost_free_orphan_time_s = 3600;
time_t rrdhost_free_ephemeral_time_s = 86400;

RRDHOST *find_host_by_node_id(char *node_id) {

    ND_UUID node_uuid;
    if (unlikely(!node_id || uuid_parse(node_id, node_uuid.uuid)))
        return NULL;

    RRDHOST *host, *ret = NULL;
    dfe_start_read(rrdhost_root_index, host) {
        if (UUIDeq(host->node_id, node_uuid)) {
            ret = host;
            break;
        }
    }
    dfe_done(host);

    return ret;
}

// ----------------------------------------------------------------------------
// RRDHOST indexes management

DICTIONARY *rrdhost_root_index = NULL;
static DICTIONARY *rrdhost_root_index_hostname = NULL;

static inline void rrdhost_init() {
    if(unlikely(!rrdhost_root_index)) {
        rrdhost_root_index = dictionary_create_advanced(
            DICT_OPTION_NAME_LINK_DONT_CLONE | DICT_OPTION_VALUE_LINK_DONT_CLONE | DICT_OPTION_DONT_OVERWRITE_VALUE,
            &dictionary_stats_category_rrdhost, 0);
    }

    if(unlikely(!rrdhost_root_index_hostname)) {
        rrdhost_root_index_hostname = dictionary_create_advanced(
            DICT_OPTION_NAME_LINK_DONT_CLONE | DICT_OPTION_VALUE_LINK_DONT_CLONE | DICT_OPTION_DONT_OVERWRITE_VALUE,
            &dictionary_stats_category_rrdhost, 0);
    }
}

RRDHOST_ACQUIRED *rrdhost_find_and_acquire(const char *machine_guid) {
    return (RRDHOST_ACQUIRED *)dictionary_get_and_acquire_item(rrdhost_root_index, machine_guid);
}

RRDHOST *rrdhost_acquired_to_rrdhost(RRDHOST_ACQUIRED *rha) {
    if(unlikely(!rha))
        return NULL;

    return (RRDHOST *) dictionary_acquired_item_value((const DICTIONARY_ITEM *)rha);
}

void rrdhost_acquired_release(RRDHOST_ACQUIRED *rha) {
    if(unlikely(!rha))
        return;

    dictionary_acquired_item_release(rrdhost_root_index, (const DICTIONARY_ITEM *)rha);
}

// ----------------------------------------------------------------------------
// RRDHOST index by UUID

inline size_t rrdhost_hosts_available(void) {
    return dictionary_entries(rrdhost_root_index);
}

inline RRDHOST *rrdhost_find_by_guid(const char *guid) {
    return dictionary_get(rrdhost_root_index, guid);
}

static inline RRDHOST *rrdhost_index_add_by_guid(RRDHOST *host) {
    RRDHOST *ret_machine_guid = dictionary_set(rrdhost_root_index, host->machine_guid, host, sizeof(RRDHOST));
    if(ret_machine_guid == host)
        rrdhost_option_set(host, RRDHOST_OPTION_INDEXED_MACHINE_GUID);
    else {
        rrdhost_option_clear(host, RRDHOST_OPTION_INDEXED_MACHINE_GUID);
        nd_log(NDLS_DAEMON, NDLP_NOTICE,
               "RRDHOST: host with machine guid '%s' is already indexed. Not adding it again.",
               host->machine_guid);
    }

    return host;
}

static void rrdhost_index_del_by_guid(RRDHOST *host) {
    if(rrdhost_option_check(host, RRDHOST_OPTION_INDEXED_MACHINE_GUID)) {
        if(!dictionary_del(rrdhost_root_index, host->machine_guid))
        nd_log(NDLS_DAEMON, NDLP_NOTICE,
               "RRDHOST: failed to delete machine guid '%s' from index",
               host->machine_guid);

        rrdhost_option_clear(host, RRDHOST_OPTION_INDEXED_MACHINE_GUID);
    }
}

// ----------------------------------------------------------------------------
// RRDHOST index by hostname

inline RRDHOST *rrdhost_find_by_hostname(const char *hostname) {
    if(unlikely(!strcmp(hostname, "localhost")))
        return localhost;

    return dictionary_get(rrdhost_root_index_hostname, hostname);
}

static inline void rrdhost_index_del_hostname(RRDHOST *host) {
    if(unlikely(!host->hostname)) return;

    if(rrdhost_option_check(host, RRDHOST_OPTION_INDEXED_HOSTNAME)) {
        if(!dictionary_del(rrdhost_root_index_hostname, rrdhost_hostname(host)))
            nd_log(NDLS_DAEMON, NDLP_NOTICE,
                   "RRDHOST: failed to delete hostname '%s' from index",
                   rrdhost_hostname(host));

        rrdhost_option_clear(host, RRDHOST_OPTION_INDEXED_HOSTNAME);
    }
}

static inline RRDHOST *rrdhost_index_add_hostname(RRDHOST *host) {
    if(!host->hostname) return host;

    RRDHOST *ret_hostname = dictionary_set(rrdhost_root_index_hostname, rrdhost_hostname(host), host, sizeof(RRDHOST));
    if(ret_hostname == host)
        rrdhost_option_set(host, RRDHOST_OPTION_INDEXED_HOSTNAME);
    else {
        //have the same hostname but it's not the same host
        //keep the new one only if the old one is orphan or archived
        if (rrdhost_flag_check(ret_hostname, RRDHOST_FLAG_ORPHAN) || rrdhost_flag_check(ret_hostname, RRDHOST_FLAG_ARCHIVED)) {
            rrdhost_index_del_hostname(ret_hostname);
            rrdhost_index_add_hostname(host);
        }
    }

    return host;
}

// ----------------------------------------------------------------------------
// RRDHOST - internal helpers

static inline void rrdhost_init_hostname(RRDHOST *host, const char *hostname, bool add_to_index) {
    if(unlikely(hostname && !*hostname)) hostname = NULL;

    if(host->hostname && hostname && !strcmp(rrdhost_hostname(host), hostname))
        return;

    rrdhost_index_del_hostname(host);

    STRING *old = host->hostname;
    host->hostname = string_strdupz(hostname?hostname:"localhost");
    string_freez(old);

    if(add_to_index)
        rrdhost_index_add_hostname(host);
}

static inline void rrdhost_init_os(RRDHOST *host, const char *os) {
    if(host->os && os && !strcmp(rrdhost_os(host), os))
        return;

    STRING *old = host->os;
    host->os = string_strdupz(os?os:"unknown");
    string_freez(old);
}

static inline void rrdhost_init_timezone(RRDHOST *host, const char *timezone, const char *abbrev_timezone, int32_t utc_offset) {
    if (host->timezone && timezone && !strcmp(rrdhost_timezone(host), timezone) && host->abbrev_timezone && abbrev_timezone &&
        !strcmp(rrdhost_abbrev_timezone(host), abbrev_timezone) && host->utc_offset == utc_offset)
        return;

    STRING *old = host->timezone;
    host->timezone = string_strdupz((timezone && *timezone)?timezone:"unknown");
    string_freez(old);

    old = (void *)host->abbrev_timezone;
    host->abbrev_timezone = string_strdupz((abbrev_timezone && *abbrev_timezone) ? abbrev_timezone : "UTC");
    string_freez(old);

    host->utc_offset = utc_offset;
}

void set_host_properties(RRDHOST *host, int update_every, RRD_MEMORY_MODE memory_mode,
                         const char *registry_hostname, const char *os, const char *tzone,
                         const char *abbrev_tzone, int32_t utc_offset, const char *prog_name,
                         const char *prog_version)
{

    host->rrd_update_every = update_every;
    host->rrd_memory_mode = memory_mode;

    rrdhost_init_os(host, os);
    rrdhost_init_timezone(host, tzone, abbrev_tzone, utc_offset);

    host->program_name = string_strdupz((prog_name && *prog_name) ? prog_name : "unknown");
    host->program_version = string_strdupz((prog_version && *prog_version) ? prog_version : "unknown");
    host->registry_hostname = string_strdupz((registry_hostname && *registry_hostname) ? registry_hostname : rrdhost_hostname(host));
}

// ----------------------------------------------------------------------------
// RRDHOST - add a host

static void rrdhost_initialize_rrdpush_sender(RRDHOST *host,
                                              unsigned int rrdpush_enabled,
                                              const char *rrdpush_destination,
                                              const char *rrdpush_api_key,
                                              const char *rrdpush_send_charts_matching
) {
    if(rrdhost_flag_check(host, RRDHOST_FLAG_RRDPUSH_SENDER_INITIALIZED)) return;

    if(rrdpush_enabled && rrdpush_destination && *rrdpush_destination && rrdpush_api_key && *rrdpush_api_key) {
        rrdhost_flag_set(host, RRDHOST_FLAG_RRDPUSH_SENDER_INITIALIZED);

        rrdhost_streaming_sender_structures_init(host);

        host->sender->ssl = NETDATA_SSL_UNSET_CONNECTION;

        host->rrdpush.send.destination = strdupz(rrdpush_destination);
        rrdpush_destinations_init(host);

        host->rrdpush.send.api_key = strdupz(rrdpush_api_key);
        host->rrdpush.send.charts_matching = simple_pattern_create(rrdpush_send_charts_matching, NULL,
                                                                   SIMPLE_PATTERN_EXACT, true);

        rrdhost_option_set(host, RRDHOST_OPTION_SENDER_ENABLED);
    }
    else
        rrdhost_option_clear(host, RRDHOST_OPTION_SENDER_ENABLED);
}

#ifdef ENABLE_DBENGINE
//
//  true on success
//
static bool create_dbengine_directory(RRDHOST *host, const char *dbenginepath)
{
    int ret = mkdir(dbenginepath, 0775);
    if (ret != 0 && errno != EEXIST) {
        nd_log(NDLS_DAEMON, NDLP_CRIT, "Host '%s': cannot create directory '%s'", rrdhost_hostname(host), dbenginepath);
        return false;
    }
    return true;
}

static RRDHOST *prepare_host_for_unittest(RRDHOST *host)
{
    char dbenginepath[FILENAME_MAX + 1];

    if (host->cache_dir)
        freez(host->cache_dir);

    snprintfz(dbenginepath, FILENAME_MAX, "%s/%s", netdata_configured_cache_dir, host->machine_guid);
    host->cache_dir = strdupz(dbenginepath);

    int ret = 0;

    bool initialized;
    if ((initialized = create_dbengine_directory(host, dbenginepath))) {
        snprintfz(dbenginepath, FILENAME_MAX, "%s/dbengine", host->cache_dir);

        if ((initialized = create_dbengine_directory(host, dbenginepath))) {
            host->db[0].mode = RRD_MEMORY_MODE_DBENGINE;
            host->db[0].eng = storage_engine_get(host->db[0].mode);
            host->db[0].tier_grouping = get_tier_grouping(0);

            ret = rrdeng_init(
                (struct rrdengine_instance **)&host->db[0].si,
                dbenginepath,
                default_rrdeng_disk_quota_mb,
                0,
                0); // may fail here for legacy dbengine initialization

            initialized = (ret == 0);

            if (initialized)
                rrdeng_readiness_wait((struct rrdengine_instance *)host->db[0].si);
        }
    }

    if (!initialized) {
        nd_log(
            NDLS_DAEMON,
            NDLP_CRIT,
            "Host '%s': cannot initialize host with machine guid '%s'. Failed to initialize DB engine at '%s'.",
            rrdhost_hostname(host),
            host->machine_guid,
            host->cache_dir);

        rrd_wrlock();
        rrdhost_free___while_having_rrd_wrlock(host, true);
        rrd_wrunlock();
        return NULL;
    }
    return host;
}
#endif

static RRDHOST *rrdhost_create(
        const char *hostname,
        const char *registry_hostname,
        const char *guid,
        const char *os,
        const char *timezone,
        const char *abbrev_timezone,
        int32_t utc_offset,
        const char *prog_name,
        const char *prog_version,
        int update_every,
        long entries,
        RRD_MEMORY_MODE memory_mode,
        unsigned int health_enabled,
        unsigned int rrdpush_enabled,
        const char *rrdpush_destination,
        const char *rrdpush_api_key,
        const char *rrdpush_send_charts_matching,
        bool rrdpush_enable_replication,
        time_t rrdpush_seconds_to_replicate,
        time_t rrdpush_replication_step,
        struct rrdhost_system_info *system_info,
        int is_localhost,
        bool archived
) {
    if(memory_mode == RRD_MEMORY_MODE_DBENGINE && !dbengine_enabled) {
        nd_log(NDLS_DAEMON, NDLP_ERR,
               "memory mode 'dbengine' is not enabled, but host '%s' is configured for it. Falling back to 'alloc'",
               hostname);

        memory_mode = RRD_MEMORY_MODE_ALLOC;
    }

    RRDHOST *host = callocz(1, sizeof(RRDHOST));
    __atomic_add_fetch(&netdata_buffers_statistics.rrdhost_allocations_size, sizeof(RRDHOST), __ATOMIC_RELAXED);

    strncpyz(host->machine_guid, guid, GUID_LEN + 1);

    set_host_properties(
        host,
        (update_every > 0) ? update_every : 1,
        memory_mode,
        registry_hostname,
        os,
        timezone,
        abbrev_timezone,
        utc_offset,
        prog_name,
        prog_version);

    rrdhost_init_hostname(host, hostname, false);

    host->rrd_history_entries        = align_entries_to_pagesize(memory_mode, entries);
    host->health.health_enabled      = ((memory_mode == RRD_MEMORY_MODE_NONE)) ? 0 : health_enabled;

    spinlock_init(&host->receiver_lock);

    if (likely(!archived)) {
        rrd_functions_host_init(host);
        host->last_connected = now_realtime_sec();
        host->rrdlabels = rrdlabels_create();
        rrdhost_initialize_rrdpush_sender(
            host, rrdpush_enabled, rrdpush_destination, rrdpush_api_key, rrdpush_send_charts_matching);
    }

    if(rrdpush_enable_replication)
        rrdhost_option_set(host, RRDHOST_OPTION_REPLICATION);
    else
        rrdhost_option_clear(host, RRDHOST_OPTION_REPLICATION);

    host->rrdpush_seconds_to_replicate = rrdpush_seconds_to_replicate;
    host->rrdpush_replication_step = rrdpush_replication_step;
    host->rrdpush_receiver_replication_percent = 100.0;

    switch(memory_mode) {
        default:
        case RRD_MEMORY_MODE_ALLOC:
        case RRD_MEMORY_MODE_RAM:
            if(host->rrdpush_seconds_to_replicate > (time_t) host->rrd_history_entries * (time_t) host->rrd_update_every)
                host->rrdpush_seconds_to_replicate = (time_t) host->rrd_history_entries * (time_t) host->rrd_update_every;
            break;

        case RRD_MEMORY_MODE_DBENGINE:
            break;
    }

    host->system_info = system_info;

    rrdset_index_init(host);

    if(is_localhost)
        host->cache_dir  = strdupz(netdata_configured_cache_dir);

    // this is also needed for custom host variables - not only health
    if(!host->rrdvars)
        host->rrdvars = rrdvariables_create();

    if (likely(!uuid_parse(host->machine_guid, host->host_id.uuid)))
        sql_load_node_id(host);
    else
        error_report("Host machine GUID %s is not valid", host->machine_guid);

    rrdcalc_rrdhost_index_init(host);

    if (host->rrd_memory_mode == RRD_MEMORY_MODE_DBENGINE) {
#ifdef ENABLE_DBENGINE
        if (unittest_running) {
            host = prepare_host_for_unittest(host);
            if (!host)
                return NULL;
        }
        else {
            for(size_t tier = 0; tier < storage_tiers ; tier++) {
                host->db[tier].mode = RRD_MEMORY_MODE_DBENGINE;
                host->db[tier].eng = storage_engine_get(host->db[tier].mode);
                host->db[tier].si = (STORAGE_INSTANCE *)multidb_ctx[tier];
                host->db[tier].tier_grouping = get_tier_grouping(tier);
            }
        }
#else
        fatal("RRD_MEMORY_MODE_DBENGINE is not supported in this platform.");
#endif
    }
    else {
        host->db[0].mode = host->rrd_memory_mode;
        host->db[0].eng = storage_engine_get(host->db[0].mode);
        host->db[0].si = NULL;
        host->db[0].tier_grouping = get_tier_grouping(0);

#ifdef ENABLE_DBENGINE
        // the first tier is reserved for the non-dbengine modes
        for(size_t tier = 1; tier < storage_tiers ; tier++) {
            host->db[tier].mode = RRD_MEMORY_MODE_DBENGINE;
            host->db[tier].eng = storage_engine_get(host->db[tier].mode);
            host->db[tier].si = (STORAGE_INSTANCE *) multidb_ctx[tier];
            host->db[tier].tier_grouping = get_tier_grouping(tier);
        }
#endif
    }

    // ------------------------------------------------------------------------
    // init new ML host and update system_info to let upstreams know
    // about ML functionality
    //

    if (is_localhost && host->system_info) {
        host->system_info->ml_capable = ml_capable();
        host->system_info->ml_enabled = ml_enabled(host);
        host->system_info->mc_version = metric_correlations_version;
    }

    // ------------------------------------------------------------------------
    // link it and add it to the index

    rrd_wrlock();

    RRDHOST *t = rrdhost_index_add_by_guid(host);
    if(t != host) {
        nd_log(NDLS_DAEMON, NDLP_NOTICE,
               "Host '%s': cannot add host with machine guid '%s' to index. It already exists as host '%s' with machine guid '%s'.",
               rrdhost_hostname(host), host->machine_guid, rrdhost_hostname(t), t->machine_guid);

        if (!is_localhost)
            rrdhost_free___while_having_rrd_wrlock(host, true);

        rrd_wrunlock();
        return NULL;
    }

    rrdhost_index_add_hostname(host);

    if(is_localhost)
        DOUBLE_LINKED_LIST_PREPEND_ITEM_UNSAFE(localhost, host, prev, next);
    else
        DOUBLE_LINKED_LIST_APPEND_ITEM_UNSAFE(localhost, host, prev, next);

    rrd_wrunlock();

    // ------------------------------------------------------------------------

    nd_log(NDLS_DAEMON, NDLP_INFO,
           "Host '%s' (at registry as '%s') with guid '%s' initialized"
           ", os '%s'"
           ", timezone '%s'"
           ", program_name '%s'"
           ", program_version '%s'"
           ", update every %d"
           ", memory mode %s"
           ", history entries %d"
           ", streaming %s"
           " (to '%s' with api key '%s')"
           ", health %s"
           ", cache_dir '%s'"
           ", alarms default handler '%s'"
           ", alarms default recipient '%s'"
         , rrdhost_hostname(host)
         , rrdhost_registry_hostname(host)
         , host->machine_guid
         , rrdhost_os(host)
         , rrdhost_timezone(host)
         , rrdhost_program_name(host)
         , rrdhost_program_version(host)
         , host->rrd_update_every
         , rrd_memory_mode_name(host->rrd_memory_mode)
         , host->rrd_history_entries
         , rrdhost_has_rrdpush_sender_enabled(host)?"enabled":"disabled"
         , host->rrdpush.send.destination?host->rrdpush.send.destination:""
         , host->rrdpush.send.api_key?host->rrdpush.send.api_key:""
         , host->health.health_enabled?"enabled":"disabled"
         , host->cache_dir
         , string2str(host->health.health_default_exec)
         , string2str(host->health.health_default_recipient)
    );

    if(!archived) {
        metaqueue_host_update_info(host);
        rrdhost_load_rrdcontext_data(host);
//        rrdhost_flag_set(host, RRDHOST_FLAG_METADATA_INFO | RRDHOST_FLAG_METADATA_UPDATE);
        ml_host_new(host);
    } else
        rrdhost_flag_set(host, RRDHOST_FLAG_PENDING_CONTEXT_LOAD | RRDHOST_FLAG_ARCHIVED | RRDHOST_FLAG_ORPHAN);

    return host;
}

static void rrdhost_update(RRDHOST *host
                           , const char *hostname
                           , const char *registry_hostname
                           , const char *guid
                           , const char *os
                           , const char *timezone
                           , const char *abbrev_timezone
                           , int32_t utc_offset
                           , const char *prog_name
                           , const char *prog_version
                           , int update_every
                           , long history
                           , RRD_MEMORY_MODE mode
                           , unsigned int health_enabled
                           , unsigned int rrdpush_enabled
                           , const char *rrdpush_destination
                           , const char *rrdpush_api_key
                           , const char *rrdpush_send_charts_matching
                           , bool rrdpush_enable_replication
                           , time_t rrdpush_seconds_to_replicate
                           , time_t rrdpush_replication_step
                           , struct rrdhost_system_info *system_info
)
{
    UNUSED(guid);

    spinlock_lock(&host->rrdhost_update_lock);

    host->health.health_enabled = (mode == RRD_MEMORY_MODE_NONE) ? 0 : health_enabled;

    {
        struct rrdhost_system_info *old = host->system_info;
        host->system_info = system_info;
        rrdhost_flag_set(host, RRDHOST_FLAG_METADATA_INFO | RRDHOST_FLAG_METADATA_CLAIMID | RRDHOST_FLAG_METADATA_UPDATE);
        rrdhost_system_info_free(old);
    }

    rrdhost_init_os(host, os);
    rrdhost_init_timezone(host, timezone, abbrev_timezone, utc_offset);

    string_freez(host->registry_hostname);
    host->registry_hostname = string_strdupz((registry_hostname && *registry_hostname)?registry_hostname:hostname);

    if(strcmp(rrdhost_hostname(host), hostname) != 0) {
        nd_log(NDLS_DAEMON, NDLP_WARNING,
               "Host '%s' has been renamed to '%s'. If this is not intentional it may mean multiple hosts are using the same machine_guid.",
               rrdhost_hostname(host), hostname);

        rrdhost_init_hostname(host, hostname, true);
    } else {
        rrdhost_index_add_hostname(host);
    }

    if(strcmp(rrdhost_program_name(host), prog_name) != 0) {
        nd_log(NDLS_DAEMON, NDLP_NOTICE,
               "Host '%s' switched program name from '%s' to '%s'",
               rrdhost_hostname(host), rrdhost_program_name(host),
            prog_name);

        STRING *t = host->program_name;
        host->program_name = string_strdupz(prog_name);
        string_freez(t);
    }

    if(strcmp(rrdhost_program_version(host), prog_version) != 0) {
        nd_log(NDLS_DAEMON, NDLP_NOTICE,
               "Host '%s' switched program version from '%s' to '%s'",
               rrdhost_hostname(host), rrdhost_program_version(host),
            prog_version);

        STRING *t = host->program_version;
        host->program_version = string_strdupz(prog_version);
        string_freez(t);
    }

    if(host->rrd_update_every != update_every)
        nd_log(NDLS_DAEMON, NDLP_WARNING,
               "Host '%s' has an update frequency of %d seconds, but the wanted one is %d seconds. "
               "Restart netdata here to apply the new settings.",
               rrdhost_hostname(host), host->rrd_update_every, update_every);

    if(host->rrd_memory_mode != mode)
        nd_log(NDLS_DAEMON, NDLP_WARNING,
               "Host '%s' has memory mode '%s', but the wanted one is '%s'. "
               "Restart netdata here to apply the new settings.",
               rrdhost_hostname(host),
               rrd_memory_mode_name(host->rrd_memory_mode),
               rrd_memory_mode_name(mode));

    else if(host->rrd_memory_mode != RRD_MEMORY_MODE_DBENGINE && host->rrd_history_entries < history)
        nd_log(NDLS_DAEMON, NDLP_WARNING,
               "Host '%s' has history of %d entries, but the wanted one is %ld entries. "
               "Restart netdata here to apply the new settings.",
               rrdhost_hostname(host),
               host->rrd_history_entries,
               history);

    if(!host->rrdvars)
        host->rrdvars = rrdvariables_create();

    host->last_connected = now_realtime_sec();

    if (rrdhost_flag_check(host, RRDHOST_FLAG_ARCHIVED)) {
        rrdhost_flag_clear(host, RRDHOST_FLAG_ARCHIVED);

        rrd_functions_host_init(host);

        if(!host->rrdlabels)
            host->rrdlabels = rrdlabels_create();

        if (!host->rrdset_root_index)
            rrdset_index_init(host);

        rrdhost_initialize_rrdpush_sender(host,
                                   rrdpush_enabled,
                                   rrdpush_destination,
                                   rrdpush_api_key,
                                   rrdpush_send_charts_matching);

        rrdcalc_rrdhost_index_init(host);

        if(rrdpush_enable_replication)
            rrdhost_option_set(host, RRDHOST_OPTION_REPLICATION);
        else
            rrdhost_option_clear(host, RRDHOST_OPTION_REPLICATION);

        host->rrdpush_seconds_to_replicate = rrdpush_seconds_to_replicate;
        host->rrdpush_replication_step = rrdpush_replication_step;

        ml_host_new(host);

        rrdhost_load_rrdcontext_data(host);
        nd_log(NDLS_DAEMON, NDLP_DEBUG,
               "Host %s is not in archived mode anymore",
               rrdhost_hostname(host));
    }

    spinlock_unlock(&host->rrdhost_update_lock);
}

RRDHOST *rrdhost_find_or_create(
      const char *hostname
    , const char *registry_hostname
    , const char *guid
    , const char *os
    , const char *timezone
    , const char *abbrev_timezone
    , int32_t utc_offset
    , const char *prog_name
    , const char *prog_version
    , int update_every
    , long history
    , RRD_MEMORY_MODE mode
    , unsigned int health_enabled
    , unsigned int rrdpush_enabled
    , const char *rrdpush_destination
    , const char *rrdpush_api_key
    , const char *rrdpush_send_charts_matching
    , bool rrdpush_enable_replication
    , time_t rrdpush_seconds_to_replicate
    , time_t rrdpush_replication_step
    , struct rrdhost_system_info *system_info
    , bool archived
) {
    RRDHOST *host = rrdhost_find_by_guid(guid);
    if (unlikely(host && host->rrd_memory_mode != mode && rrdhost_flag_check(host, RRDHOST_FLAG_ARCHIVED))) {

        if (likely(!archived && rrdhost_flag_check(host, RRDHOST_FLAG_PENDING_CONTEXT_LOAD)))
            return host;

        /* If a legacy memory mode instantiates all dbengine state must be discarded to avoid inconsistencies */
        nd_log(NDLS_DAEMON, NDLP_INFO,
               "Archived host '%s' has memory mode '%s', but the wanted one is '%s'. Discarding archived state.",
               rrdhost_hostname(host),
               rrd_memory_mode_name(host->rrd_memory_mode),
               rrd_memory_mode_name(mode));

        rrd_wrlock();
        rrdhost_free___while_having_rrd_wrlock(host, true);
        host = NULL;
        rrd_wrunlock();
    }

    if(!host) {
        host = rrdhost_create(
                hostname
                , registry_hostname
                , guid
                , os
                , timezone
                , abbrev_timezone
                , utc_offset
                , prog_name
                , prog_version
                , update_every
                , history
                , mode
                , health_enabled
                , rrdpush_enabled
                , rrdpush_destination
                , rrdpush_api_key
                , rrdpush_send_charts_matching
                , rrdpush_enable_replication
                , rrdpush_seconds_to_replicate
                , rrdpush_replication_step
                , system_info
                , 0
                , archived
        );
    }
    else {
        if (likely(!rrdhost_flag_check(host, RRDHOST_FLAG_PENDING_CONTEXT_LOAD)))
            rrdhost_update(host
               , hostname
               , registry_hostname
               , guid
               , os
               , timezone
               , abbrev_timezone
               , utc_offset
               , prog_name
               , prog_version
               , update_every
               , history
               , mode
               , health_enabled
               , rrdpush_enabled
               , rrdpush_destination
               , rrdpush_api_key
               , rrdpush_send_charts_matching
               , rrdpush_enable_replication
               , rrdpush_seconds_to_replicate
               , rrdpush_replication_step
               , system_info);
    }

    return host;
}

inline int rrdhost_should_be_removed(RRDHOST *host, RRDHOST *protected_host, time_t now_s) {
    if(host != protected_host
       && host != localhost
       && rrdhost_receiver_replicating_charts(host) == 0
       && rrdhost_sender_replicating_charts(host) == 0
       && rrdhost_flag_check(host, RRDHOST_FLAG_ORPHAN)
       && !rrdhost_flag_check(host, RRDHOST_FLAG_PENDING_CONTEXT_LOAD)
       && !host->receiver
       && host->child_disconnected_time
       && host->child_disconnected_time + rrdhost_free_orphan_time_s < now_s)
        return 1;

    return 0;
}

// ----------------------------------------------------------------------------
// RRDHOST global / startup initialization

#ifdef ENABLE_DBENGINE
struct dbengine_initialization {
    ND_THREAD *thread;
    char path[FILENAME_MAX + 1];
    int disk_space_mb;
    size_t retention_seconds;
    size_t tier;
    int ret;
};

typedef struct rrd_alert_prototype {
    struct rrd_alert_match match;
    struct rrd_alert_config config;

    struct {
        uint32_t uses;
        bool enabled;
        bool is_on_disk;
        SPINLOCK spinlock;
        struct rrd_alert_prototype *prev, *next;
    } _internal;
} RRD_ALERT_PROTOTYPE;

void *dbengine_tier_init(void *ptr) {
    struct dbengine_initialization *dbi = ptr;
    dbi->ret = rrdeng_init(NULL, dbi->path, dbi->disk_space_mb, dbi->tier, dbi->retention_seconds);
    return ptr;
}

RRD_BACKFILL get_dbengine_backfill(RRD_BACKFILL backfill)
{
    const char *bf = config_get(
        CONFIG_SECTION_DB,
        "dbengine tier backfill",
        backfill == RRD_BACKFILL_NEW  ? "new" :
        backfill == RRD_BACKFILL_FULL ? "full" :
                                        "none");

    if (strcmp(bf, "new") == 0)
        backfill = RRD_BACKFILL_NEW;
    else if (strcmp(bf, "full") == 0)
        backfill = RRD_BACKFILL_FULL;
    else if (strcmp(bf, "none") == 0)
        backfill = RRD_BACKFILL_NONE;
    else {
        nd_log(NDLS_DAEMON, NDLP_WARNING, "DBENGINE: unknown backfill value '%s', assuming 'new'", bf);
        config_set(CONFIG_SECTION_DB, "dbengine tier backfill", "new");
        backfill = RRD_BACKFILL_NEW;
    }
    return backfill;
}

#endif

static void dbengine_init(const char *hostname) {
#ifdef ENABLE_DBENGINE

    use_direct_io = config_get_boolean(CONFIG_SECTION_DB, "dbengine use direct io", use_direct_io);

    unsigned read_num = (unsigned)config_get_number(CONFIG_SECTION_DB, "dbengine pages per extent", DEFAULT_PAGES_PER_EXTENT);
    if (read_num > 0 && read_num <= DEFAULT_PAGES_PER_EXTENT)
        rrdeng_pages_per_extent = read_num;
    else {
        nd_log(NDLS_DAEMON, NDLP_WARNING,
               "Invalid dbengine pages per extent %u given. Using %u.",
               read_num, rrdeng_pages_per_extent);

        config_set_number(CONFIG_SECTION_DB, "dbengine pages per extent", rrdeng_pages_per_extent);
    }

    storage_tiers = config_get_number(CONFIG_SECTION_DB, "storage tiers", storage_tiers);
    if(storage_tiers < 1) {
        nd_log(NDLS_DAEMON, NDLP_WARNING, "At least 1 storage tier is required. Assuming 1.");

        storage_tiers = 1;
        config_set_number(CONFIG_SECTION_DB, "storage tiers", storage_tiers);
    }
    if(storage_tiers > RRD_STORAGE_TIERS) {
        nd_log(NDLS_DAEMON, NDLP_WARNING,
               "Up to %d storage tier are supported. Assuming %d.",
               RRD_STORAGE_TIERS, RRD_STORAGE_TIERS);

        storage_tiers = RRD_STORAGE_TIERS;
        config_set_number(CONFIG_SECTION_DB, "storage tiers", storage_tiers);
    }

    new_dbengine_defaults =
        (!legacy_multihost_db_space &&
         !config_exists(CONFIG_SECTION_DB, "dbengine tier 1 update every iterations") &&
         !config_exists(CONFIG_SECTION_DB, "dbengine tier 2 update every iterations") &&
         !config_exists(CONFIG_SECTION_DB, "dbengine tier 3 update every iterations") &&
         !config_exists(CONFIG_SECTION_DB, "dbengine tier 4 update every iterations") &&
         !config_exists(CONFIG_SECTION_DB, "dbengine tier 1 retention size") &&
         !config_exists(CONFIG_SECTION_DB, "dbengine tier 2 retention size") &&
         !config_exists(CONFIG_SECTION_DB, "dbengine tier 3 retention size") &&
         !config_exists(CONFIG_SECTION_DB, "dbengine tier 4 retention size"));

    default_backfill = get_dbengine_backfill(RRD_BACKFILL_NEW);
    char dbengineconfig[200 + 1];

    size_t grouping_iterations = default_rrd_update_every;
    storage_tiers_grouping_iterations[0] = default_rrd_update_every;

    for (size_t tier = 1; tier < storage_tiers; tier++) {
        grouping_iterations = storage_tiers_grouping_iterations[tier];
        snprintfz(dbengineconfig, sizeof(dbengineconfig) - 1, "dbengine tier %zu update every iterations", tier);
        grouping_iterations = config_get_number(CONFIG_SECTION_DB, dbengineconfig, grouping_iterations);
        if(grouping_iterations < 2) {
            grouping_iterations = 2;
            config_set_number(CONFIG_SECTION_DB, dbengineconfig, grouping_iterations);
            nd_log(NDLS_DAEMON, NDLP_WARNING,
                   "DBENGINE on '%s': 'dbegnine tier %zu update every iterations' cannot be less than 2. Assuming 2.",
                   hostname, tier);
        }
        storage_tiers_grouping_iterations[tier] = grouping_iterations;
    }

    default_multidb_disk_quota_mb = (int) config_get_size_mb(CONFIG_SECTION_DB, "dbengine tier 0 retention size", RRDENG_DEFAULT_TIER_DISK_SPACE_MB);
    if(default_multidb_disk_quota_mb && default_multidb_disk_quota_mb < RRDENG_MIN_DISK_SPACE_MB) {
        netdata_log_error("Invalid disk space %d for tier 0 given. Defaulting to %d.", default_multidb_disk_quota_mb, RRDENG_MIN_DISK_SPACE_MB);
        default_multidb_disk_quota_mb = RRDENG_MIN_DISK_SPACE_MB;
        config_set_size_mb(CONFIG_SECTION_DB, "dbengine tier 0 retention size", default_multidb_disk_quota_mb);
    }

#ifdef OS_WINDOWS
    // FIXME: for whatever reason joining the initialization threads
    // fails on Windows.
    bool parallel_initialization = false;
#else
    bool parallel_initialization = (storage_tiers <= (size_t)get_netdata_cpus()) ? true : false;
#endif

    struct dbengine_initialization tiers_init[RRD_STORAGE_TIERS] = {};

    size_t created_tiers = 0;
    char dbenginepath[FILENAME_MAX + 1];

    for (size_t tier = 0; tier < storage_tiers; tier++) {

        if (tier == 0)
            snprintfz(dbenginepath, FILENAME_MAX, "%s/dbengine", netdata_configured_cache_dir);
        else
            snprintfz(dbenginepath, FILENAME_MAX, "%s/dbengine-tier%zu", netdata_configured_cache_dir, tier);

        int ret = mkdir(dbenginepath, 0775);
        if (ret != 0 && errno != EEXIST) {
            nd_log(NDLS_DAEMON, NDLP_CRIT, "DBENGINE on '%s': cannot create directory '%s'", hostname, dbenginepath);
            continue;
        }

        int disk_space_mb = tier ? RRDENG_DEFAULT_TIER_DISK_SPACE_MB : default_multidb_disk_quota_mb;
        snprintfz(dbengineconfig, sizeof(dbengineconfig) - 1, "dbengine tier %zu retention size", tier);
        disk_space_mb = config_get_size_mb(CONFIG_SECTION_DB, dbengineconfig, disk_space_mb);

        snprintfz(dbengineconfig, sizeof(dbengineconfig) - 1, "dbengine tier %zu retention time", tier);
        storage_tiers_retention_days[tier] = config_get_duration_days(
            CONFIG_SECTION_DB, dbengineconfig, new_dbengine_defaults ? storage_tiers_retention_days[tier] : 0);

        tiers_init[tier].disk_space_mb = (int) disk_space_mb;
        tiers_init[tier].tier = tier;
        tiers_init[tier].retention_seconds = (size_t) (86400.0 * storage_tiers_retention_days[tier]);
        strncpyz(tiers_init[tier].path, dbenginepath, FILENAME_MAX);
        tiers_init[tier].ret = 0;

        if(parallel_initialization) {
            char tag[NETDATA_THREAD_TAG_MAX + 1];
            snprintfz(tag, NETDATA_THREAD_TAG_MAX, "DBENGINIT[%zu]", tier);
            tiers_init[tier].thread = nd_thread_create(tag, NETDATA_THREAD_OPTION_JOINABLE, dbengine_tier_init, &tiers_init[tier]);
        }
        else
            dbengine_tier_init(&tiers_init[tier]);
    }

    for(size_t tier = 0; tier < storage_tiers ;tier++) {
        if(parallel_initialization)
            nd_thread_join(tiers_init[tier].thread);

        if(tiers_init[tier].ret != 0) {
            nd_log(NDLS_DAEMON, NDLP_ERR,
                   "DBENGINE on '%s': Failed to initialize multi-host database tier %zu on path '%s'",
                   hostname, tiers_init[tier].tier, tiers_init[tier].path);
        }
        else if(created_tiers == tier)
            created_tiers++;
    }

    if(created_tiers && created_tiers < storage_tiers) {
        nd_log(NDLS_DAEMON, NDLP_WARNING,
               "DBENGINE on '%s': Managed to create %zu tiers instead of %zu. Continuing with %zu available.",
               hostname, created_tiers, storage_tiers, created_tiers);

        storage_tiers = created_tiers;
    }
    else if(!created_tiers)
        fatal("DBENGINE on '%s', failed to initialize databases at '%s'.", hostname, netdata_configured_cache_dir);

    for(size_t tier = 0; tier < storage_tiers ;tier++)
        rrdeng_readiness_wait(multidb_ctx[tier]);

    calculate_tier_disk_space_percentage();

    dbengine_enabled = true;
#else
    storage_tiers = config_get_number(CONFIG_SECTION_DB, "storage tiers", 1);
    if(storage_tiers != 1) {
        nd_log(NDLS_DAEMON, NDLP_WARNING,
               "DBENGINE is not available on '%s', so only 1 database tier can be supported.",
               hostname);

        storage_tiers = 1;
        config_set_number(CONFIG_SECTION_DB, "storage tiers", storage_tiers);
    }
    dbengine_enabled = false;
#endif
}

void api_v1_management_init(void);

int rrd_init(const char *hostname, struct rrdhost_system_info *system_info, bool unittest) {
    rrdhost_init();

    if (unlikely(sql_init_meta_database(DB_CHECK_NONE, system_info ? 0 : 1))) {
        if (default_rrd_memory_mode == RRD_MEMORY_MODE_DBENGINE) {
            set_late_analytics_variables(system_info);
            fatal("Failed to initialize SQLite");
        }

        nd_log(NDLS_DAEMON, NDLP_DEBUG,
               "Skipping SQLITE metadata initialization since memory mode is not dbengine");
    }

    if (unlikely(sql_init_context_database(system_info ? 0 : 1))) {
        error_report("Failed to initialize context metadata database");
    }

    if (unlikely(unittest)) {
        dbengine_enabled = true;
    }
    else {
        rrdpush_init();

        if (default_rrd_memory_mode == RRD_MEMORY_MODE_DBENGINE || rrdpush_receiver_needs_dbengine()) {
            nd_log(NDLS_DAEMON, NDLP_DEBUG,
                   "DBENGINE: Initializing ...");

            dbengine_init(hostname);
        }
        else
            storage_tiers = 1;

        if (!dbengine_enabled) {
            if (storage_tiers > 1) {
                nd_log(NDLS_DAEMON, NDLP_WARNING,
                       "dbengine is not enabled, but %zu tiers have been requested. Resetting tiers to 1",
                       storage_tiers);

                storage_tiers = 1;
            }

            if (default_rrd_memory_mode == RRD_MEMORY_MODE_DBENGINE) {
                nd_log(NDLS_DAEMON, NDLP_WARNING,
                       "dbengine is not enabled, but it has been given as the default db mode. "
                       "Resetting db mode to alloc");

                default_rrd_memory_mode = RRD_MEMORY_MODE_ALLOC;
            }
        }
    }

    if(!unittest)
        metadata_sync_init();

    localhost = rrdhost_create(
            hostname
            , registry_get_this_machine_hostname()
            , registry_get_this_machine_guid()
            , os_type
            , netdata_configured_timezone
            , netdata_configured_abbrev_timezone
            , netdata_configured_utc_offset
            , program_name
            , NETDATA_VERSION
            , default_rrd_update_every
            , default_rrd_history_entries
            , default_rrd_memory_mode
            , health_plugin_enabled()
            , default_rrdpush_enabled
            , default_rrdpush_destination
            , default_rrdpush_api_key
            , default_rrdpush_send_charts_matching
            , default_rrdpush_enable_replication
            , default_rrdpush_seconds_to_replicate
            , default_rrdpush_replication_step
            , system_info
            , 1
            , 0
    );

    if (unlikely(!localhost))
        return 1;

    dyncfg_host_init(localhost);

    if(!unittest)
        health_plugin_init();

    global_functions_add();

    if (likely(system_info)) {
        detect_machine_guid_change(&localhost->host_id.uuid);
        sql_aclk_sync_init();
        api_v1_management_init();
    }

    return 0;
}

// ----------------------------------------------------------------------------
// RRDHOST - free

void rrdhost_system_info_free(struct rrdhost_system_info *system_info) {
    if(likely(system_info)) {
        __atomic_sub_fetch(&netdata_buffers_statistics.rrdhost_allocations_size, sizeof(struct rrdhost_system_info), __ATOMIC_RELAXED);

        freez(system_info->cloud_provider_type);
        freez(system_info->cloud_instance_type);
        freez(system_info->cloud_instance_region);
        freez(system_info->host_os_name);
        freez(system_info->host_os_id);
        freez(system_info->host_os_id_like);
        freez(system_info->host_os_version);
        freez(system_info->host_os_version_id);
        freez(system_info->host_os_detection);
        freez(system_info->host_cores);
        freez(system_info->host_cpu_freq);
        freez(system_info->host_cpu_model);
        freez(system_info->host_ram_total);
        freez(system_info->host_disk_space);
        freez(system_info->container_os_name);
        freez(system_info->container_os_id);
        freez(system_info->container_os_id_like);
        freez(system_info->container_os_version);
        freez(system_info->container_os_version_id);
        freez(system_info->container_os_detection);
        freez(system_info->kernel_name);
        freez(system_info->kernel_version);
        freez(system_info->architecture);
        freez(system_info->virtualization);
        freez(system_info->virt_detection);
        freez(system_info->container);
        freez(system_info->container_detection);
        freez(system_info->is_k8s_node);
        freez(system_info->install_type);
        freez(system_info->prebuilt_arch);
        freez(system_info->prebuilt_dist);
        freez(system_info);
    }
}

static void rrdhost_streaming_sender_structures_init(RRDHOST *host)
{
    if (host->sender)
        return;

    host->sender = callocz(1, sizeof(*host->sender));
    __atomic_add_fetch(&netdata_buffers_statistics.rrdhost_senders, sizeof(*host->sender), __ATOMIC_RELAXED);

    host->sender->host = host;
    host->sender->buffer = cbuffer_new(CBUFFER_INITIAL_SIZE, 1024 * 1024, &netdata_buffers_statistics.cbuffers_streaming);
    host->sender->capabilities = stream_our_capabilities(host, true);

    host->sender->rrdpush_sender_pipe[PIPE_READ] = -1;
    host->sender->rrdpush_sender_pipe[PIPE_WRITE] = -1;
    host->sender->rrdpush_sender_socket  = -1;
    host->sender->disabled_capabilities = STREAM_CAP_NONE;

    if(!default_rrdpush_compression_enabled)
        host->sender->disabled_capabilities |= STREAM_CAP_COMPRESSIONS_AVAILABLE;

    spinlock_init(&host->sender->spinlock);
    replication_init_sender(host->sender);
}

static void rrdhost_streaming_sender_structures_free(RRDHOST *host)
{
    rrdhost_option_clear(host, RRDHOST_OPTION_SENDER_ENABLED);

    if (unlikely(!host->sender))
        return;

    rrdpush_sender_thread_stop(host, STREAM_HANDSHAKE_DISCONNECT_HOST_CLEANUP, true); // stop a possibly running thread
    cbuffer_free(host->sender->buffer);

    rrdpush_compressor_destroy(&host->sender->compressor);

    replication_cleanup_sender(host->sender);

    __atomic_sub_fetch(&netdata_buffers_statistics.rrdhost_senders, sizeof(*host->sender), __ATOMIC_RELAXED);

    freez(host->sender);
    host->sender = NULL;
    rrdhost_flag_clear(host, RRDHOST_FLAG_RRDPUSH_SENDER_INITIALIZED);
}

void rrdhost_free___while_having_rrd_wrlock(RRDHOST *host, bool force) {
    if(!host) return;

    if (netdata_exit || force) {
        nd_log(NDLS_DAEMON, NDLP_DEBUG,
               "RRD: 'host:%s' freeing memory...",
               rrdhost_hostname(host));

        // ------------------------------------------------------------------------
        // first remove it from the indexes, so that it will not be discoverable

        rrdhost_index_del_hostname(host);
        rrdhost_index_del_by_guid(host);

        if (host->prev)
            DOUBLE_LINKED_LIST_REMOVE_ITEM_UNSAFE(localhost, host, prev, next);
    }

    // ------------------------------------------------------------------------

    rrdhost_stream_path_clear(host, true);

    // ------------------------------------------------------------------------
    // clean up streaming chart slots

    rrdhost_pluginsd_send_chart_slots_free(host);
    rrdhost_pluginsd_receive_chart_slots_free(host);

    // ------------------------------------------------------------------------
    // clean up streaming

    rrdhost_streaming_sender_structures_free(host);

    if (netdata_exit || force)
        stop_streaming_receiver(host, STREAM_HANDSHAKE_DISCONNECT_HOST_CLEANUP);


    // ------------------------------------------------------------------------
    // clean up alarms

    rrdcalc_delete_all(host);

    // delete all the RRDSETs of the host
    rrdset_index_destroy(host);
    rrdcalc_rrdhost_index_destroy(host);

    // cleanup ML resources
    ml_host_delete(host);

    freez(host->exporting_flags);

    health_alarm_log_free(host);

    if (!netdata_exit && !force) {
        nd_log(NDLS_DAEMON, NDLP_DEBUG,
               "RRD: 'host:%s' is now in archive mode...",
               rrdhost_hostname(host));

        rrdhost_flag_set(host, RRDHOST_FLAG_ARCHIVED | RRDHOST_FLAG_ORPHAN);
        return;
    }

    // ------------------------------------------------------------------------
    // free it

    rrdlabels_destroy(host->rrdlabels);
    string_freez(host->os);
    string_freez(host->timezone);
    string_freez(host->abbrev_timezone);
    string_freez(host->program_name);
    string_freez(host->program_version);
    rrdhost_system_info_free(host->system_info);
    freez(host->cache_dir);
    freez(host->rrdpush.send.api_key);
    freez(host->rrdpush.send.destination);
    rrdpush_destinations_free(host);
    string_freez(host->health.health_default_exec);
    string_freez(host->health.health_default_recipient);
    string_freez(host->registry_hostname);
    simple_pattern_free(host->rrdpush.send.charts_matching);

    rrd_functions_host_destroy(host);
    rrdvariables_destroy(host->rrdvars);
    if (host == localhost)
        health_plugin_destroy();

    rrdhost_destroy_rrdcontexts(host);

    string_freez(host->hostname);
    __atomic_sub_fetch(&netdata_buffers_statistics.rrdhost_allocations_size, sizeof(RRDHOST), __ATOMIC_RELAXED);

    freez(host);
}

void rrdhost_free_all(void) {
    rrd_wrlock();

    /* Make sure child-hosts are released before the localhost. */
    while(localhost && localhost->next)
        rrdhost_free___while_having_rrd_wrlock(localhost->next, true);

    if(localhost)
        rrdhost_free___while_having_rrd_wrlock(localhost, true);

    rrd_wrunlock();
}

void rrd_finalize_collection_for_all_hosts(void) {
    RRDHOST *host;
    dfe_start_reentrant(rrdhost_root_index, host) {
        rrdhost_finalize_collection(host);
    }
    dfe_done(host);
}

struct rrdhost_system_info *rrdhost_labels_to_system_info(RRDLABELS *labels) {
    struct rrdhost_system_info *info = callocz(1, sizeof(struct rrdhost_system_info));
    info->hops = 1;

    rrdlabels_get_value_strdup_or_null(labels, &info->cloud_provider_type, "_cloud_provider_type");
    rrdlabels_get_value_strdup_or_null(labels, &info->cloud_instance_type, "_cloud_instance_type");
    rrdlabels_get_value_strdup_or_null(labels, &info->cloud_instance_region, "_cloud_instance_region");
    rrdlabels_get_value_strdup_or_null(labels, &info->host_os_name, "_os_name");
    rrdlabels_get_value_strdup_or_null(labels, &info->host_os_version, "_os_version");
    rrdlabels_get_value_strdup_or_null(labels, &info->kernel_version, "_kernel_version");
    rrdlabels_get_value_strdup_or_null(labels, &info->host_cores, "_system_cores");
    rrdlabels_get_value_strdup_or_null(labels, &info->host_cpu_freq, "_system_cpu_freq");
    rrdlabels_get_value_strdup_or_null(labels, &info->host_cpu_model, "_system_cpu_model");
    rrdlabels_get_value_strdup_or_null(labels, &info->host_ram_total, "_system_ram_total");
    rrdlabels_get_value_strdup_or_null(labels, &info->host_disk_space, "_system_disk_space");
    rrdlabels_get_value_strdup_or_null(labels, &info->architecture, "_architecture");
    rrdlabels_get_value_strdup_or_null(labels, &info->virtualization, "_virtualization");
    rrdlabels_get_value_strdup_or_null(labels, &info->container, "_container");
    rrdlabels_get_value_strdup_or_null(labels, &info->container_detection, "_container_detection");
    rrdlabels_get_value_strdup_or_null(labels, &info->virt_detection, "_virt_detection");
    rrdlabels_get_value_strdup_or_null(labels, &info->is_k8s_node, "_is_k8s_node");
    rrdlabels_get_value_strdup_or_null(labels, &info->install_type, "_install_type");
    rrdlabels_get_value_strdup_or_null(labels, &info->prebuilt_arch, "_prebuilt_arch");
    rrdlabels_get_value_strdup_or_null(labels, &info->prebuilt_dist, "_prebuilt_dist");

    return info;
}

static void rrdhost_load_auto_labels(void) {
    RRDLABELS *labels = localhost->rrdlabels;

    if (localhost->system_info->cloud_provider_type)
        rrdlabels_add(labels, "_cloud_provider_type", localhost->system_info->cloud_provider_type, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->cloud_instance_type)
        rrdlabels_add(labels, "_cloud_instance_type", localhost->system_info->cloud_instance_type, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->cloud_instance_region)
        rrdlabels_add(labels, "_cloud_instance_region", localhost->system_info->cloud_instance_region, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->host_os_name)
        rrdlabels_add(labels, "_os_name", localhost->system_info->host_os_name, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->host_os_version)
        rrdlabels_add(labels, "_os_version", localhost->system_info->host_os_version, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->kernel_version)
        rrdlabels_add(labels, "_kernel_version", localhost->system_info->kernel_version, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->host_cores)
        rrdlabels_add(labels, "_system_cores", localhost->system_info->host_cores, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->host_cpu_freq)
        rrdlabels_add(labels, "_system_cpu_freq", localhost->system_info->host_cpu_freq, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->host_cpu_model)
        rrdlabels_add(labels, "_system_cpu_model", localhost->system_info->host_cpu_model, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->host_ram_total)
        rrdlabels_add(labels, "_system_ram_total", localhost->system_info->host_ram_total, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->host_disk_space)
        rrdlabels_add(labels, "_system_disk_space", localhost->system_info->host_disk_space, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->architecture)
        rrdlabels_add(labels, "_architecture", localhost->system_info->architecture, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->virtualization)
        rrdlabels_add(labels, "_virtualization", localhost->system_info->virtualization, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->container)
        rrdlabels_add(labels, "_container", localhost->system_info->container, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->container_detection)
        rrdlabels_add(labels, "_container_detection", localhost->system_info->container_detection, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->virt_detection)
        rrdlabels_add(labels, "_virt_detection", localhost->system_info->virt_detection, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->is_k8s_node)
        rrdlabels_add(labels, "_is_k8s_node", localhost->system_info->is_k8s_node, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->install_type)
        rrdlabels_add(labels, "_install_type", localhost->system_info->install_type, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->prebuilt_arch)
        rrdlabels_add(labels, "_prebuilt_arch", localhost->system_info->prebuilt_arch, RRDLABEL_SRC_AUTO);

    if (localhost->system_info->prebuilt_dist)
        rrdlabels_add(labels, "_prebuilt_dist", localhost->system_info->prebuilt_dist, RRDLABEL_SRC_AUTO);

    add_aclk_host_labels();

    // The source should be CONF, but when it is set, these labels are exported by default ('send configured labels' in exporting.conf).
    // Their export seems to break exporting to Graphite, see https://github.com/netdata/netdata/issues/14084.

    int is_ephemeral = appconfig_get_boolean(&netdata_config, CONFIG_SECTION_GLOBAL, "is ephemeral node", CONFIG_BOOLEAN_NO);
    rrdlabels_add(labels, "_is_ephemeral", is_ephemeral ? "true" : "false", RRDLABEL_SRC_AUTO);

    int has_unstable_connection = appconfig_get_boolean(&netdata_config, CONFIG_SECTION_GLOBAL, "has unstable connection", CONFIG_BOOLEAN_NO);
    rrdlabels_add(labels, "_has_unstable_connection", has_unstable_connection ? "true" : "false", RRDLABEL_SRC_AUTO);

    rrdlabels_add(labels, "_is_parent", (localhost->connected_children_count > 0) ? "true" : "false", RRDLABEL_SRC_AUTO);

    rrdlabels_add(labels, "_hostname", string2str(localhost->hostname), RRDLABEL_SRC_AUTO);
    rrdlabels_add(labels, "_os", string2str(localhost->os), RRDLABEL_SRC_AUTO);

    if (localhost->rrdpush.send.destination)
        rrdlabels_add(labels, "_streams_to", localhost->rrdpush.send.destination, RRDLABEL_SRC_AUTO);
}

void rrdhost_set_is_parent_label(void) {
    int count = __atomic_load_n(&localhost->connected_children_count, __ATOMIC_RELAXED);

    if (count == 0 || count == 1) {
        RRDLABELS *labels = localhost->rrdlabels;
        rrdlabels_add(labels, "_is_parent", (count) ? "true" : "false", RRDLABEL_SRC_AUTO);

        //queue a node info
        aclk_queue_node_info(localhost, false);
    }
}

static bool config_label_cb(void *data __maybe_unused, const char *name, const char *value) {
    rrdlabels_add(localhost->rrdlabels, name, value, RRDLABEL_SRC_CONFIG);
    return true;
}

static void rrdhost_load_config_labels(void) {
    int status = config_load(NULL, 1, CONFIG_SECTION_HOST_LABEL);
    if(!status) {
        char *filename = CONFIG_DIR "/" CONFIG_FILENAME;
        nd_log(NDLS_DAEMON, NDLP_WARNING,
               "RRDLABEL: Cannot reload the configuration file '%s', using labels in memory",
               filename);
    }

    appconfig_foreach_value_in_section(&netdata_config, CONFIG_SECTION_HOST_LABEL, config_label_cb, NULL);
}

static void rrdhost_load_kubernetes_labels(void) {
    char label_script[sizeof(char) * (strlen(netdata_configured_primary_plugins_dir) + strlen("get-kubernetes-labels.sh") + 2)];
    sprintf(label_script, "%s/%s", netdata_configured_primary_plugins_dir, "get-kubernetes-labels.sh");

    if (unlikely(access(label_script, R_OK) != 0)) {
        nd_log(NDLS_DAEMON, NDLP_ERR,
               "Kubernetes pod label fetching script %s not found.",
               label_script);

        return;
    }

    POPEN_INSTANCE *instance = spawn_popen_run(label_script);
    if(!instance) return;

    char buffer[1000 + 1];
    while (fgets(buffer, 1000, spawn_popen_stdout(instance)) != NULL)
        rrdlabels_add_pair(localhost->rrdlabels, buffer, RRDLABEL_SRC_AUTO|RRDLABEL_SRC_K8S);

    // Non-zero exit code means that all the script output is error messages. We've shown already any message that didn't include a ':'
    // Here we'll inform with an ERROR that the script failed, show whatever (if anything) was added to the list of labels, free the memory and set the return to null
    int rc = spawn_popen_wait(instance);
    if(rc)
        nd_log(NDLS_DAEMON, NDLP_ERR,
               "%s exited abnormally. Failed to get kubernetes labels.",
               label_script);
}

void reload_host_labels(void) {
    if(!localhost->rrdlabels)
        localhost->rrdlabels = rrdlabels_create();

    rrdlabels_unmark_all(localhost->rrdlabels);

    // priority is important here
    rrdhost_load_config_labels();
    rrdhost_load_kubernetes_labels();
    rrdhost_load_auto_labels();

    rrdhost_flag_set(localhost,RRDHOST_FLAG_METADATA_LABELS | RRDHOST_FLAG_METADATA_UPDATE);

    rrdpush_send_host_labels(localhost);
}

void rrdhost_finalize_collection(RRDHOST *host) {
    ND_LOG_STACK lgs[] = {
        ND_LOG_FIELD_TXT(NDF_NIDL_NODE, rrdhost_hostname(host)),
        ND_LOG_FIELD_END(),
    };
    ND_LOG_STACK_PUSH(lgs);

    nd_log(NDLS_DAEMON, NDLP_DEBUG,
           "RRD: 'host:%s' stopping data collection...",
           rrdhost_hostname(host));

    RRDSET *st;
    rrdset_foreach_read(st, host)
        rrdset_finalize_collection(st, true);
    rrdset_foreach_done(st);
}

// ----------------------------------------------------------------------------
// RRDHOST - set system info from environment variables
// system_info fields must be heap allocated or NULL
int rrdhost_set_system_info_variable(struct rrdhost_system_info *system_info, char *name, char *value) {
    int res = 0;

    if (!strcmp(name, "NETDATA_PROTOCOL_VERSION"))
        return res;
    else if(!strcmp(name, "NETDATA_INSTANCE_CLOUD_TYPE")){
        freez(system_info->cloud_provider_type);
        system_info->cloud_provider_type = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_INSTANCE_CLOUD_INSTANCE_TYPE")){
        freez(system_info->cloud_instance_type);
        system_info->cloud_instance_type = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_INSTANCE_CLOUD_INSTANCE_REGION")){
        freez(system_info->cloud_instance_region);
        system_info->cloud_instance_region = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_CONTAINER_OS_NAME")){
        freez(system_info->container_os_name);
        system_info->container_os_name = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_CONTAINER_OS_ID")){
        freez(system_info->container_os_id);
        system_info->container_os_id = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_CONTAINER_OS_ID_LIKE")){
        freez(system_info->container_os_id_like);
        system_info->container_os_id_like = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_CONTAINER_OS_VERSION")){
        freez(system_info->container_os_version);
        system_info->container_os_version = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_CONTAINER_OS_VERSION_ID")){
        freez(system_info->container_os_version_id);
        system_info->container_os_version_id = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_CONTAINER_OS_DETECTION")){
        freez(system_info->container_os_detection);
        system_info->container_os_detection = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_HOST_OS_NAME")){
        freez(system_info->host_os_name);
        system_info->host_os_name = strdupz(value);
        json_fix_string(system_info->host_os_name);
    }
    else if(!strcmp(name, "NETDATA_HOST_OS_ID")){
        freez(system_info->host_os_id);
        system_info->host_os_id = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_HOST_OS_ID_LIKE")){
        freez(system_info->host_os_id_like);
        system_info->host_os_id_like = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_HOST_OS_VERSION")){
        freez(system_info->host_os_version);
        system_info->host_os_version = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_HOST_OS_VERSION_ID")){
        freez(system_info->host_os_version_id);
        system_info->host_os_version_id = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_HOST_OS_DETECTION")){
        freez(system_info->host_os_detection);
        system_info->host_os_detection = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_SYSTEM_KERNEL_NAME")){
        freez(system_info->kernel_name);
        system_info->kernel_name = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_SYSTEM_CPU_LOGICAL_CPU_COUNT")){
        freez(system_info->host_cores);
        system_info->host_cores = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_SYSTEM_CPU_FREQ")){
        freez(system_info->host_cpu_freq);
        system_info->host_cpu_freq = strdupz(value);
    }
    else if (!strcmp(name, "NETDATA_SYSTEM_CPU_MODEL")){
        freez(system_info->host_cpu_model);
        system_info->host_cpu_model = strdupz(value);
    } 
    else if(!strcmp(name, "NETDATA_SYSTEM_TOTAL_RAM")){
        freez(system_info->host_ram_total);
        system_info->host_ram_total = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_SYSTEM_TOTAL_DISK_SIZE")){
        freez(system_info->host_disk_space);
        system_info->host_disk_space = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_SYSTEM_KERNEL_VERSION")){
        freez(system_info->kernel_version);
        system_info->kernel_version = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_SYSTEM_ARCHITECTURE")){
        freez(system_info->architecture);
        system_info->architecture = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_SYSTEM_VIRTUALIZATION")){
        freez(system_info->virtualization);
        system_info->virtualization = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_SYSTEM_VIRT_DETECTION")){
        freez(system_info->virt_detection);
        system_info->virt_detection = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_SYSTEM_CONTAINER")){
        freez(system_info->container);
        system_info->container = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_SYSTEM_CONTAINER_DETECTION")){
        freez(system_info->container_detection);
        system_info->container_detection = strdupz(value);
    }
    else if(!strcmp(name, "NETDATA_HOST_IS_K8S_NODE")){
        freez(system_info->is_k8s_node);
        system_info->is_k8s_node = strdupz(value);
    }
    else if (!strcmp(name, "NETDATA_SYSTEM_CPU_VENDOR"))
        return res;
    else if (!strcmp(name, "NETDATA_SYSTEM_CPU_DETECTION"))
        return res;
    else if (!strcmp(name, "NETDATA_SYSTEM_RAM_DETECTION"))
        return res;
    else if (!strcmp(name, "NETDATA_SYSTEM_DISK_DETECTION"))
        return res;
    else if (!strcmp(name, "NETDATA_CONTAINER_IS_OFFICIAL_IMAGE"))
        return res;
    else {
        res = 1;
    }

    return res;
}

static NETDATA_DOUBLE rrdhost_sender_replication_completion_unsafe(RRDHOST *host, time_t now, size_t *instances) {
    size_t charts = rrdhost_sender_replicating_charts(host);
    NETDATA_DOUBLE completion;
    if(!charts || !host->sender || !host->sender->replication.oldest_request_after_t)
        completion = 100.0;
    else if(!host->sender->replication.latest_completed_before_t || host->sender->replication.latest_completed_before_t < host->sender->replication.oldest_request_after_t)
        completion = 0.0;
    else {
        time_t total = now - host->sender->replication.oldest_request_after_t;
        time_t current = host->sender->replication.latest_completed_before_t - host->sender->replication.oldest_request_after_t;
        completion = (NETDATA_DOUBLE) current * 100.0 / (NETDATA_DOUBLE) total;
    }

    *instances = charts;

    return completion;
}

bool rrdhost_matches_window(RRDHOST *host, time_t after, time_t before, time_t now) {
    time_t first_time_s, last_time_s;
    rrdhost_retention(host, now, rrdhost_is_online(host), &first_time_s, &last_time_s);
    return query_matches_retention(after, before, first_time_s, last_time_s, 0);
}

bool rrdhost_state_cloud_emulation(RRDHOST *host) {
    return rrdhost_is_online(host);
}

void rrdhost_status(RRDHOST *host, time_t now, RRDHOST_STATUS *s) {
    memset(s, 0, sizeof(*s));

    s->host = host;
    s->now = now;

    RRDHOST_FLAGS flags = __atomic_load_n(&host->flags, __ATOMIC_RELAXED);

    // --- dyncfg ---

    s->dyncfg.status = dyncfg_available_for_rrdhost(host) ? RRDHOST_DYNCFG_STATUS_AVAILABLE : RRDHOST_DYNCFG_STATUS_UNAVAILABLE;

    // --- db ---

    bool online = rrdhost_is_online(host);

    rrdhost_retention(host, now, online, &s->db.first_time_s, &s->db.last_time_s);
    s->db.metrics = host->rrdctx.metrics;
    s->db.instances = host->rrdctx.instances;
    s->db.contexts = dictionary_entries(host->rrdctx.contexts);
    if(!s->db.first_time_s || !s->db.last_time_s || !s->db.metrics || !s->db.instances || !s->db.contexts ||
            (flags & (RRDHOST_FLAG_PENDING_CONTEXT_LOAD)))
        s->db.status = RRDHOST_DB_STATUS_INITIALIZING;
    else
        s->db.status = RRDHOST_DB_STATUS_QUERYABLE;

    s->db.mode = host->rrd_memory_mode;

    // --- ingest ---

    s->ingest.since = MAX(host->child_connect_time, host->child_disconnected_time);
    s->ingest.reason = (online) ? STREAM_HANDSHAKE_NEVER : host->rrdpush_last_receiver_exit_reason;

    spinlock_lock(&host->receiver_lock);
    s->ingest.hops = (host->system_info ? host->system_info->hops : (host == localhost) ? 0 : 1);
    bool has_receiver = false;
    if (host->receiver) {
        has_receiver = true;
        s->ingest.replication.instances = rrdhost_receiver_replicating_charts(host);
        s->ingest.replication.completion = host->rrdpush_receiver_replication_percent;
        s->ingest.replication.in_progress = s->ingest.replication.instances > 0;

        s->ingest.capabilities = host->receiver->capabilities;
        s->ingest.peers = socket_peers(host->receiver->fd);
        s->ingest.ssl = SSL_connection(&host->receiver->ssl);
    }
    spinlock_unlock(&host->receiver_lock);

    if (online) {
        if(s->db.status == RRDHOST_DB_STATUS_INITIALIZING)
            s->ingest.status = RRDHOST_INGEST_STATUS_INITIALIZING;

        else if (host == localhost || rrdhost_option_check(host, RRDHOST_OPTION_VIRTUAL_HOST)) {
            s->ingest.status = RRDHOST_INGEST_STATUS_ONLINE;
            s->ingest.since = netdata_start_time;
        }

        else if (s->ingest.replication.in_progress)
            s->ingest.status = RRDHOST_INGEST_STATUS_REPLICATING;

        else
            s->ingest.status = RRDHOST_INGEST_STATUS_ONLINE;
    }
    else {
        if (!s->ingest.since) {
            s->ingest.status = RRDHOST_INGEST_STATUS_ARCHIVED;
            s->ingest.since = s->db.last_time_s;
        }

        else
            s->ingest.status = RRDHOST_INGEST_STATUS_OFFLINE;
    }

    if(host == localhost)
        s->ingest.type = RRDHOST_INGEST_TYPE_LOCALHOST;
    else if(has_receiver || rrdhost_flag_set(host, RRDHOST_FLAG_RRDPUSH_RECEIVER_DISCONNECTED))
        s->ingest.type = RRDHOST_INGEST_TYPE_CHILD;
    else if(rrdhost_option_check(host, RRDHOST_OPTION_VIRTUAL_HOST))
        s->ingest.type = RRDHOST_INGEST_TYPE_VIRTUAL;
    else
        s->ingest.type = RRDHOST_INGEST_TYPE_ARCHIVED;

    s->ingest.id = host->rrdpush_receiver_connection_counter;

    if(!s->ingest.since)
        s->ingest.since = netdata_start_time;

    if(s->ingest.status == RRDHOST_INGEST_STATUS_ONLINE)
        s->db.liveness = RRDHOST_DB_LIVENESS_LIVE;
    else
        s->db.liveness = RRDHOST_DB_LIVENESS_STALE;

    // --- stream ---

    if (!host->sender) {
        s->stream.status = RRDHOST_STREAM_STATUS_DISABLED;
        s->stream.hops = s->ingest.hops + 1;
    }
    else {
        sender_lock(host->sender);

        s->stream.since = host->sender->last_state_since_t;
        s->stream.peers = socket_peers(host->sender->rrdpush_sender_socket);
        s->stream.ssl = SSL_connection(&host->sender->ssl);

        memcpy(s->stream.sent_bytes_on_this_connection_per_type,
               host->sender->sent_bytes_on_this_connection_per_type,
            MIN(sizeof(s->stream.sent_bytes_on_this_connection_per_type),
                sizeof(host->sender->sent_bytes_on_this_connection_per_type)));

        if (rrdhost_flag_check(host, RRDHOST_FLAG_RRDPUSH_SENDER_CONNECTED)) {
            s->stream.hops = host->sender->hops;
            s->stream.reason = STREAM_HANDSHAKE_NEVER;
            s->stream.capabilities = host->sender->capabilities;

            s->stream.replication.completion = rrdhost_sender_replication_completion_unsafe(host, now, &s->stream.replication.instances);
            s->stream.replication.in_progress = s->stream.replication.instances > 0;

            if(s->stream.replication.in_progress)
                s->stream.status = RRDHOST_STREAM_STATUS_REPLICATING;
            else
                s->stream.status = RRDHOST_STREAM_STATUS_ONLINE;

            s->stream.compression = host->sender->compressor.initialized;
        }
        else {
            s->stream.status = RRDHOST_STREAM_STATUS_OFFLINE;
            s->stream.hops = s->ingest.hops + 1;
            s->stream.reason = host->sender->exit.reason;
        }

        sender_unlock(host->sender);
    }

    s->stream.id = host->rrdpush_sender_connection_counter;

    if(!s->stream.since)
        s->stream.since = netdata_start_time;

    // --- ml ---

    if(ml_host_get_host_status(host, &s->ml.metrics)) {
        s->ml.type = RRDHOST_ML_TYPE_SELF;

        if(s->ingest.status == RRDHOST_INGEST_STATUS_OFFLINE || s->ingest.status == RRDHOST_INGEST_STATUS_ARCHIVED)
            s->ml.status = RRDHOST_ML_STATUS_OFFLINE;
        else
            s->ml.status = RRDHOST_ML_STATUS_RUNNING;
    }
    else if(stream_has_capability(&s->ingest, STREAM_CAP_DATA_WITH_ML)) {
        s->ml.type = RRDHOST_ML_TYPE_RECEIVED;
        s->ml.status = RRDHOST_ML_STATUS_RUNNING;
    }
    else {
        // does not receive ML, does not run ML
        s->ml.type = RRDHOST_ML_TYPE_DISABLED;
        s->ml.status = RRDHOST_ML_STATUS_DISABLED;
    }

    // --- health ---

    if(host->health.health_enabled) {
        if(flags & RRDHOST_FLAG_PENDING_HEALTH_INITIALIZATION)
            s->health.status = RRDHOST_HEALTH_STATUS_INITIALIZING;
        else {
            s->health.status = RRDHOST_HEALTH_STATUS_RUNNING;

            RRDCALC *rc;
            foreach_rrdcalc_in_rrdhost_read(host, rc) {
                if (unlikely(!rc->rrdset || !rc->rrdset->last_collected_time.tv_sec))
                    continue;

                switch (rc->status) {
                    default:
                    case RRDCALC_STATUS_REMOVED:
                        break;

                    case RRDCALC_STATUS_CLEAR:
                        s->health.alerts.clear++;
                        break;

                    case RRDCALC_STATUS_WARNING:
                        s->health.alerts.warning++;
                        break;

                    case RRDCALC_STATUS_CRITICAL:
                        s->health.alerts.critical++;
                        break;

                    case RRDCALC_STATUS_UNDEFINED:
                        s->health.alerts.undefined++;
                        break;

                    case RRDCALC_STATUS_UNINITIALIZED:
                        s->health.alerts.uninitialized++;
                        break;
                }
            }
            foreach_rrdcalc_in_rrdhost_done(rc);
        }
    }
    else
        s->health.status = RRDHOST_HEALTH_STATUS_DISABLED;
}
